Pyrrolidine → (+/-)-6-bromo-3,4-dihydro-4-oxo-spiro-[2H-(1,3)-benzoxazine-2,3'-piperidine]-1'-carboxylic acid tert-butyl ester

Participants

Reaction Conditions

Reaction Steps

1-BOC-piperidin-3-one (4.0 g, 20 mmol) was added to a mixture of 5-bromo-2-hydroxybenzamide (2.0 g, 9.2 mmol) and pyrrolidine (0.76 ml, 9.2 mmol) in MeOH (7.5 ml), and the reaction mixture was heated to 70° C. by MW (closed vessel) for 5 h. The solution was then concentrated under vacuum and the crude mixture was purified by column chromatography on silica gel (eluent: DCM/EtOAc 7:3) to give (±)-6-bromo-3,4-dihydro-4-oxo-spiro-[2H-(1,3)-benzoxazine-2,3′-piperidine]-1′-carboxylic acid tert-butyl ester (2.50 g) as a yellow solid.

Provenance & Evidence